FE modeling of glulam beams with mechanical slotted-in steel plate connections.

Abstract: The mechanical behavior of timber beams with a slotted-in steel plate connection is studied by creating a numerical model that is able to simulate the global bending behavior, the global load carrying capacity and the nonlinear plastic fastener force distribution in the connection. Experimental results from Material Testing Institute (MPA), University of Stuttgart were used to verify the simulation results from this study. The modeling of both the timber beams and the mechanical connections is performed with shell, beam and nonlinear connector elements. Three models were created, where the first model was a single-dowel double shear joint model to study the ability to use structural elements in the modeling of the test beams. It was used to simulate some of the basic failure modes in Eurocode 5 (EC5). The second model was a beam model used to simulate the bending of a jointed timber beam with a slotted-in steel plate connection, where only two connector elements were used to model the joint behavior of each dowel group. It can be used to study the global deflection and the load carrying capacity of the jointed timber beams. The third model was a combined beam-shell model where the beam elements are used for the timber parts outside the connection area and the fasteners, while the shell elements are used for the slotted-in steel plate and the timber parts within the connection area. It uses two nonlinear connectors to connect each dowel to the wood and a pure coupling constraint to connect the dowels to the slotted-in steel plate. This model can simulate the same phenomena as model two and also the development of the elasto-plastic shear force distribution in all the dowels. All the models were created using parameterized Python scripts, which makes it possible to easily change different input parameters. Most of the modeling results show good agreement with both experimental results and with calculated load carrying capacity results for individual dowels according to EC5. The use of the structural elements (beam, shell, and connector elements) was found to result in much less computational time compared to the use of solid elements.